Normal "team sites" in SharePoint are mostly about collaboration - lists, libraries, discussions, etc.. Normally each site has 1 page (it's home page) and a lot of different views on lists and libraries.

"Publishing sites" focus more on allowing you to create lots of pages in a site. They give an easier authoring experience, and allow you to control that page lifecycle (i.e. page approval). However, they add a lot of complexity that isn't always necessary for collaboration.

So it really boils down to a few things. First, when you create a Publishing site you will have complete control over the master page and page layout experience. Another words, if your requirement is to build a public facing web site you would want to create a Site Collection based off the Publishing Portal template that is available. You can control page development with the layouts that you choose to build. With Publishing you also get web parts that aren't available with a collaboration portal. These web parts include the TAble of Contents Web PArt, Content Query Web Part and the Summary Links Web Part. Out of these the CQWP becomes useful so you can roll up site collection data.

Whats nice is if you choose a collaboration portal and/or site you could always enable publishing as a feature after.

I think it comes down to your requirements. If you are going to do custom branding and master pages go Publishing. You will also get a approval workflow for content approval. If you are going to do just collaboration and worry more about this than go with the collaboration protal and/or site.

Publishing sites, in short, lets a delegated group of authors, editors and approvers (or just anyone in the business who wants control of content that will be visible to everyone) create content that must go through an approval system before it can become visible to all of it's visitors.

You can also use layout templates (called Page Layouts) to control the layout of contents on your Publishing Pages.

Content is created within the layout as it will appear on the published version, so there is no need for the authors to worry about where elements will appear on the page when it's published, as authors are entering content in pre-defined sections on the page.